$3.$ Use the above user lat$-$long$-$height position $(33\mathrm{.}8822,-117\mathrm{.}8828,150)$ for this exercise.

a$.$ Load SVpos.mat. This is a matrix of $32$ SV ECEF positions at one epoch on June $23,2022.$ Compute the line$-$of$-$sight $($LOS$)$ vectors from the user to the SVs$.$ Convert to ENU. How many of these SVs are above $0$ degrees elevation of the user?b$.$ Using the SVs that are above $0$ degrees elevation, create the observability matrix H$,$ then compute the EDOP, NDOP, HDOP, VDOP, TDOP. Use matlap code for this